Valve bag



Jan. 27, 1942. CRAWFQRD 2,270,842

VALVE BAG Filed Feb. 21, 1939 ATTORNEY Patented Jan. -27, 1942 by mesneassignments, to St. Regis Paper Company, New York, N. '31., acorporation of New York Application February El, 1939, Serial No.257,642

3 Claims.

This invention relates to valve bags, and particularly to valve bagswhere the inlet opening is securely closed after filling so that therewill be no leakage through the valve.

The primary object of the invention is to provide a bag which can befilled through a substantially restricted opening which is provided witha valve designed, to close against the exit of the filled material, andin which means are provided to prohibit the leakage from the bag of anycontents that may by change tend to sift through the valve.

In describing the invention in detail, reference is herein had t theaccompanying drawing, in which- Figure 1 is a fragmentary perspectiveview of the valve end of a 'bag formed in accordance with the presentinvention;

Figure 2 is a perspective and fragmentary view of a bag illustrating onestep in the method of forming the leakproof valve;

Figure '3 is a view similar t that depicted in Fig. 2 illustratinganother step in the method of forming said valve;

Figure 4 is a vertical sectional view of the valve construction, a feedpipe being shown in dotted lines; and

Figure 5 is a vertical sectional view of the valve construction with thefeed pipe removed and the valve in sealed relation.

Referring to said'drawing, the reference numeral l designates asubstantially tubular paper bag of multi-wall construction, beingcomposed of two or more plies of paper, the bag shown ,in the drawinghaving two plies.

desired method known in th into position. Obviously, this manner offolding the ends 5 upon the valve flap 4 aifords a trap In the formationof the valve construction forming the subject matter of the presentinvention, the tube or bagend is opened out in or more plies.

of the drawing, the valve flap 4 preferably has a length exceeding thedistance between the opposite side walls of the bag so that its oppositefree ends 5 extend outwardly beyond the depth of the bag and lieparallel to the inner side of the end flaps 2 and 3,

The innermost ply of paper of the end flap 2 is out or slit in twospaced places to form a tab 6 and a valve extension tongue I, afterwhich the tab 6 is pasted to the next ply of paper of the end flap 2 byadhesive 8. The tongue I, as shown in Fig. 3, is then folded inwardlyand its 01 the valve flap i by means of adhesive it). Thus, an extensionto the valve flap 4 is formed, the tongue extension I projectinginteriorly of the bag.

The end flap 2 is then folded down and then end flap 3 is folded downupon flap 2 in the usual manner to close the bag end, adhesive l3 beingapplied between the meeting surfaces of the end flaps 2 and 3.

The corner 85 of the bag opposite to the valve corner described may beclosed or formed by any art.

When it is desired to fillthe bag, the end of the feed pipe 20 attachedto the filling apparatus is inserted in the valve between the valve flap4 and the end flap 2, the feed pipe being positioned above the valveextension 7. After filling, the bag is removed from the feed pipepermitting the bag elements to occupy the valve sealing position shownin Fig. 5.

' It will be noted that "the feed pipe 20 is actu ally introducedbetween the side wall plies of the multi-wall bag because the valveextension tongue i is formed from the inner ply or layer of the bag.Because of the flexibility of the valve tongue 1 it will ffectivelyresist any efiort of the contents to filter or sift outwardly of the bagthrough the valve.

It may also be pounted out that the opposite ends 5 of the valve flap 4are folded upon themselves when the end flaps 2 and 3 are folded or sealpreventing the leakage of contents at this point.

While the bag herein shown and described consists of two plies of paper,it will be understood'that the bag may be formed of three, four In eventthe bag is formed of three or more plies, the valve extension tongue maybe cut or formed from one or more of the inner plies of paper.-

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and it will beapparent that various changes may be made in the form, construction andarrangement of the parts without departing from the spirit and scope ofthe invention or. sacrificing all of its material advantages, the formhereinbefore described being merely a preferred embodiment thereof.

What is claimed is: 1. A bag having walls comprising a plurality oflayers of paper and having an end closure formed outer under side pastedto the upper inner side by folding upon each other flaps formed from theends of the opposite bag walls, a flap formed from the bag walls andprojecting inwardly oi the bag beneath the folded end flaps to provide abag valve, said valve flap having a length exceeding the distancebetween said end flaps so that its opposite ends will be turned uponthemselves when the end fiaps are folded one upon the other, and aninwardly projecting extension tongue of the valve flap and permanentlysecured thereto, said extension tongue being formed from a partiallysevered section of the adjacent overlying end flap. 1

2. A bag having walls comprising a plurality of layers of paper andhaving an end closure formedby folding inward about lines approximatelyparallel with the end of the bag portions of the end of the wall of thebag to form closing flaps, one of said flaps being relatively narrow andtwo of said flaps being relatively wide and adjoining opposite sides ofsaid narrow flap and one overlapping and adhering to the other and bothbeing outside of said narrow flap, and an inner portion of one of saidwider flaps being severed from the rest of the flap which it originallyconstituted and remaining attached to the wall of the bag along saidfold line, said portion being adhered to the outer side of the narrowflap, but being free from the flaps and portions thereof outsidethereof, whereby a valve opening is provided between said portion andthe overlying overlapping flaps.

3. A bag having walls comprising a plurality of layers of paper andhaving an end closure formed by folding inward about lines approximatelyparallel with the end of the bag portions of the end f the wall of thebag to form closing flaps, one of said flaps being relatively narrow andtwo of said flaps being relatively wide and adjoining opposite sides ofsaid narrow flap and one overlapping and'adhering to the other and bothbeing outside of said narrow flap, and'an inner'portion of one of saidwider flaps being severed from the rest of the flap which it originallyconstituted and remaining attached to the wall of the 'bag along saidfold line, said portion being adhered to the outer side of the narrowflap, but being free from the flaps and portions thereof outsidethereof, whereby a valve opening is provided between said portion andthe overlying overlapping flaps, and said portion extending inward ofthe bag beyond the inner end of said narrow flap to which it is adhered.

RY CRAWFORD.

